The purpose of the contract is to 1) establish qualified clinical research units that, by building of existing research resources at the host Institution and combining the necessary expertise in clinical pharmacology and child psychiatry, can become national resources where studies ont he safety and efficacy of psychotropic medications can be conducted in a prompt and cost effective manner; and 2) fund selected research projects of particular public health significance, in particular in the area of autism and other pervasive developmental disorders, to be conducted at these units. The units, together with the already funded RUPPs will work as a network of research sites and conduct high priority clinical studies in various pediatric ages, conducting research on various aspects of pediatric psychopharmacology, including (but not limited to): dose ranges, dosing regimen, pharmacokinetics, general safety profile, efficacy and effectiveness, and effects on cognition, behavior and development. To establish research units of where clinical studies on the safety, efficacy, pharmacokinetics and pharmacodynamics of psychotropic medications can be investigated in children and adolescents, in general, and in patients suffering from autism and other pervasive developmental disorders in particular. To conduct a minimum of 2 studies at each research unit (of which one shall be a clinical efficacy trial and the other a pharmacokinetic and/or pharmacodynamic dose finding study or a pilot efficacy and tolerability study) during the 3 years of the contract. In addition, if the two year option is exercised, at least another two similar studies (i.e., one efficacy trial and one pharmacokinetic and/or pharmacodynamic dose finding study) shall be conducted. To spur the conduct of other clinical trials and studies in pediatric psychopharmacology to be funded through mechanisms other than this contract (i.e., investigator-initiated grants from federal agencies, private foundations, and pharmaceutical companies).